Emissive road marker system

ABSTRACT

A roadside marker comprises a light-emitting element, an electronic circuit connected to the light-emitting element, a battery connected to the electronic circuit, a photovoltaic cell electrically connected to the battery, and an actuator for causing the electronic circuit to transmit a signal to a remote location. A traffic alert system that includes the roadside marker, and a method of remote signals using the roadside marker, are also provided.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/786,205, filed Mar. 27, 2006, the disclosure of which is hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to road marker systems and automated emergency services notification.

BACKGROUND OF THE INVENTION

Current highway markers are of the retro-reflective type. Active or emissive markers have been proposed. For example, Published U.S. Patent Application No. 2004/0175232 and U.S. Pat. No. 5,839,816 disclose emissive highway markers. Those markers use traditional light-emitting diodes (LEDs) that degrade over time and lose power efficiency. As LEDs degrade, the wavelength of the light emitted by the LED will change, causing a shift in the color of the light produced. They also include traditional solar panels, which are typically made of glass, which is non-flexible, brittle, and measure somewhere between 4 and 10 millimeters thick. Traditional solar panels are expensive to construct and may not be durable when subjected to the vibration induced by road traffic.

Various traffic information and alerting systems have been described as in U.S. Pat. No. 6,785,606 and U.S. Pat. No. 6,728,629, but most require vehicles to be equipped with a monitoring system and include expensive roadside installations. Warning systems in vehicles can distract a driver's attention from the road at the worst possible moment. According to research by the National Highway Traffic Safety Administration (NHTSA), 80% of all accidents are related to driver distraction.

Proposed camera and night vision systems are limited to line of sight and are not capable of perceiving incidents around corners, particularly on rural roads. The majority of vehicles worldwide are not equipped with warning systems and this is not likely to change for decades. Even when in-vehicle guidance systems, for example U.S. Pat. No. 6,370,475, become more common, reckless driving and accidents will continue.

Thousands of people die or are seriously injured from road accidents when they could have been saved or had better outcomes if emergency services had arrived just. a few minutes earlier. In addition, multiple vehicle accidents occur because of a lack of warning of impending danger ahead from accidents or stopped traffic. There are traffic monitoring systems deployed in and around a few large cities, but there are none in place on highways or rural roads that can immediately and automatically notify traffic emergency authorities of traffic incidents. This is an even bigger problem in remote areas or hours of the night when traffic volume is light and when vehicle occupants might be incapacitated and unable to call for help.

The invention seeks to improve road safety by providing a cost-effective solution to these issues.

SUMMARY OF THE INVENTION

In one aspect, the invention provides a roadside marker comprising a light-emitting element, an electronic circuit connected to the light-emitting element, a battery connected to the electronic circuit, a photovoltaic cell electrically connected to the battery, and an actuator for causing the electronic circuit to transmit a signal to a remote location.

In another aspect, the invention provides a traffic alert system comprising a plurality of roadside markers each including a light-emitting element, an electronic circuit connected to the light-emitting element, a battery connected to the electronic circuit, a photovoltaic cell electrically connected to the battery, and wherein the electronic circuit is capable of transmitting signals to, and receiving signals from, one or more devices at one or more remote locations.

The invention also encompasses a method comprising the steps of placing a plurality of roadside markers in an area, wherein each of the roadside markers includes a light-emitting element, an electronic circuit connected to the light-emitting element, a battery connected to the electronic circuit, and a photovoltaic cell electrically connected to the battery; and causing the electronic circuit in at least one of the roadside markers to transmit a signal to a remote location to indicate the presence of an accident or other condition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a pictorial representation of a pavement marker.

FIG. 2 is a pictorial representation of a safety cone.

FIG. 3 is a pictorial representation of a barrel.

FIG. 4 is a pictorial representation of a plastic or concrete safety barrier, for example a “Jersey Barrier”.

FIG. 5 is a pictorial representation of a commonly used tube or curved sheet roadside marker pole.

FIG. 6 is a pictorial representation of a safety barrier.

FIG. 7 is a pictorial representation of a fold-up road warning sign.

FIG. 8 is an isometric view, partially in cross-section, of a marker constructed in accordance with an embodiment of the invention.

FIG. 9 is a pictorial representation of another embodiment of the invention.

FIG. 10 is a block diagram of a marker system constructed in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a road marker having electroluminescent properties, and including electronic control circuits. The markers may include lane markers and/or temporary or permanent roadside markers that are either free standing or attached to guardrails or other structures. The invention provides for improved visibility of such markers and a warning system for both vehicles and authorities in the event of an accident, road construction, road obstruction, or other incident.

Examples of various embodiments of the road markers of this invention include, but are not limited to, lane markers (FIG. 1), safety cones (FIG. 2), roadside and construction barrels (FIG. 3), plastic or concrete barriers (FIG. 4), various roadside poles (FIG. 5), metal, cable or plastic safety barriers (FIG. 6), and various fixed and fold-up road warning signs (FIG. 7). The invention can be embodied in a tape that is affixed to various structures.

FIG. 1 is a pictorial representation of a pavement marker constructed in accordance with an embodiment of the invention. Pavement markers are available in various colors like orange, yellow and white. Where water hydrants are located they are blue. Pavement markers constructed in accordance with an embodiment of the invention can include a tape 115 that includes an electroluminescent layer and an electronic circuit. The tape can be used in combination with the standard retro-reflectors 100.

FIG. 2 is a pictorial representation of a safety cone. FIG. 3 is a pictorial representation of a barrel. Cones and barrels can be improved by the attachment of one or more bands of the tape 115 of this invention, in addition to the standard retro-reflective tape band 120. Since each tape would be a complete unit, failure of any of the electronic components in one tape would not affect the other tapes.

FIG. 4 is a pictorial representation of a plastic or concrete safety barrier, for example a “Jersey Barrier”. Metal or plastic brackets 125 can be manufactured to support the tape 115 of this invention. These brackets can be attached to the barrier with a suitable adhesive or a nail gun. Additionally or alternatively, the tape of this invention can be applied directly to the surface 140 of such barriers.

FIG. 5 is a pictorial representation of a commonly used tube or curved sheet roadside marker pole that can be improved by the addition of the tape 115 of this invention in addition to the standard retro-reflective tape 120.

FIG. 6 is a pictorial representation of a safety barrier with the tape 115 of this invention affixed to a plastic or metal bracket 130 that is attached to the stanchion or support pillar. The tape can be used in combination with a standard retro-reflective label 120. Also or alternately, a bracket 135 can be attached in the hollow curve of a guardrail to support the photoluminescent and electroluminescent plastic tape 115 of this invention.

FIG. 7 is a pictorial representation of a fold-up road warning sign with standard reflector tape 120 shown. This could be improved by the addition of the tape 115 of this invention.

FIG. 8 is an isometric view, partially in cross-section, of a tape that can be used in markers constructed in accordance with an embodiment of the invention. The tape is manufactured as a multi-layer flexible tape that can be produced in various lengths. In the embodiment of FIG. 8, layer 210 is the top optically transparent protective film. The surface of layer 210 can be printed on.

Layer 220 is a light-emitting element, which can be constructed of an electroluminescent film, possibly of the type made by Evident Technologies, which uses quantum dot tunable electroluminescent semiconductors. The film can be tuned to emit electromagnetic radiation at any visible or infrared wavelength allowing the present invention to produce the optimum or specific colors dictated by roadway conventions, including white light. The dots can have a thickness 2 to 10 nm, allowing them to be easily rolled or folded up. They are very inexpensive to produce and have great stability. They are uniformly bright, and the brightness remains constant over the entire surface even if cut or slightly damaged.

Electroluminescent plastics use 10 times less energy than traditional LEDs and give off no heat, last longer and require no maintenance. They are non-toxic, harmless, and non-radioactive and the light activation cycle can be repeated an unlimited number of times. The electroluminescent material is so thin that photons readily transmitted through the material will excite the electrons in an underlying photovoltaic (PV) solar cell layer 230. When electroluminescent material is overlaid on solar cells, the solar cell output is improved by converting various high-energy wavelengths into more desirable wavelengths.

There are other electroluminescent plastic films that can be utilized. These could include, but are not limited to, alkaline earth metal aluminate oxide materials. These materials are preferred over zinc based luminescent materials due to their brighter initial afterglow, longer afterglow, and resistance to UV and humidity. Such materials can be chemically doped to produce infrared radiation.

Thin film polymer light-emitting diode (PLEDs) type materials or equivalents can also be used as the light-emitting element. They have advantages in that they emit full spectrum color and require a relatively small amount of power for the light produced. PLED emissive materials can be applied on a substrate by a technique derived from commercial inkjet printing. By having the option of a full color spectrum, the PLEDs can emit different colors when required to indicate different road conditions or hazards, for example blue could indicate icing, green could be fog, and red could be an accident. Yellow could indicate caution, as in roadway construction.

Layer 230 includes flexible type photovoltaic (PV) solar cells such as those developed by Evident Technologies. These PV cells use the highly efficient (over 30%) and low cost benefits of quantum dots that measure between 2 and 10 nm. Quantum dots also provide a means for tunability of the radiation absorption for optimum voltage and current generation, providing a means to optimize the present invention.

Layer 230 could also be constructed of monocrystalline silicon thin film plastic solar cell technology, for example as disclosed in U.S. Pat. No. 7,022,585, which promises to be considerably more durable and dramatically cheaper than existing silicon solar cells, and because it is less than 30 micrometers thick, can be laminated in flexible films.

Layer 260 is a thin, light, durable, flexible, safe, and affordable rechargeable Voltaflex lithium battery or equivalent. Such batteries have up to twice the power density of traditional lithium-ion batteries and can also be produced in continuous rolls, making them ideal for this application. Layer 230 is electrically connected to the thin film rechargeable batteries in layer 260 and is used to charge the batteries. This solar cell layer could also be used as the equivalent of a CDS type switch when required, allowing the units to be activated automatically in low light and turned off when appropriate if the electronic circuit is so programmed, a feature that could be useful in the vicinity of road construction.

Layer 240 is a reflective metallic layer that is designed to also work as an antenna. Layer 240 can be a metallic or metalized plastic layer that provides for a reflective backing to the solar panel, improving its efficiency and also reflecting any internally radiated light produced by the electroluminescent layer when in use. This layer can be produced in such a way that it can be optimized to perform as one or more antenna(s) for the transmission and/or reception of radio frequency signals.

Layer 270 includes a photoluminescent material such as JALITE or RTP, which is mounted on the edge of the tape structure. Such photoluminescent plastics contain purpose-designed inorganic phosphor compounds that are energized in seconds by the ultraviolet and blue light wavelength energy that is present in nearly all light sources and without the need for any electronic circuitry. At night the material emits a soft light in the visual spectrum that is conspicuous at some distance, providing an effective, roadside marking for a period of up to many hours after the sun has set. JALITE and RTP photoluminescent materials are also non-radioactive and non-toxic. They are slightly recharged by each passing vehicle, benefiting following vehicle drivers that might be a considerable distance behind and whose headlights have not yet illuminated the standard retro-reflectors as used currently. They can also be doped to provide an infrared radiation to increase visibility to various vehicle safety and guidance systems.

Layer 250 is a flexible substrate electronics circuit, also known as a flex circuit, supporting preferably ultra thin flexible components such as microprocessors, a modulator, a transceiver, rewritable memory, and a solid-state accelerometer or micro-mechanical sensor (MEMS). MEMS accelerometers are now in widespread use in the automotive industry, most commonly in air bag deployment systems, and are commonly smaller than one millimeter in size, are cheap and available in many variations including both digital and analog. The accelerometer can be used to activate the electronic circuit in the event that the marker is subjected to rapid acceleration, such as if it were involved in a crash. A consideration for selecting the appropriate MEMS accelerometer switch is the specific “G” force required to activate the electronic circuit when the marker is impacted by a vehicle, but not by low forces like wind.

Layer 250 would be placed in the most efficient position between the other layers. Flex circuits are often used as connectors in various applications where flexibility, space savings, or production constraints limit the serviceability of rigid circuit boards or hand wiring. They are common in cameras and the switch matrix of keyboards. They can use the same components as found on rigid printed circuit boards, but the film components are deposited on a flexible plastic or metal foil substrate having a thickness on the order of a few micrometers. The electronic circuit can cause the light-emitting element to operate in a variety of modes, which encompass producing light in different frequency spectrums, as well as producing light for different time periods, including pulsing or continuous operation.

A momentary switch 200 can be provided to actuate the electronic circuit. The MEMS or a momentary switch provides another advantage of the present invention in that it can be manually activated, so in the event of a breakdown, serious road hazard or medical emergency, anyone can activate the system without having to know specifically where they are. The marker can then notify authorities of the exact location of an incident and simultaneously notify following traffic of a potential hazard. This would also allow those who do not have a cell phone, or where cell phone use is not possible, to call for help from within a very short distance of stopping, as road markers are generally spaced within a few car lengths of each other. The marker could also be activated by road maintenance crews during the critically dangerous period when laying out safety cones or barrels prior to beginning road maintenance and during maintenance.

Layer 280 is an adhesive layer used to mount the tape on a structure, such as those shown in FIGS. 1-7. It is preferably a permanent adhesive so the tape is destroyed by attempted removal, preventing theft and misuse. If the tape becomes defective, a new tape can be simply placed over the top of it. The adhesive layer could be protected during manufacture by a wax-like paper that is easily removed from the adhesive before application. This wax paper could be printed with a simple label that reads, “Remove and apply this end first”. If the tape is applied to a circular object like barrels, cones or roadside marker poles so that the tape could wrap completely around the object with length to spare, the electronics end will wrap over the tape, thus ensuring that the switch 200 and antenna are not covered.

FIG. 9 is a pictorial representation of an embodiment of the present invention produced using more conventional production techniques and photoluminescent impregnated plastic. This cylindrical design is designed to be slipped over roadside markers as depicted in FIG. 5 or have a plastic plug 180 inserted into the base which is then attached by adhesive to roadside barriers, cones and signs as depicted for example in FIG. 2, FIG. 3, FIG. 4, FIG. 6, and FIG. 7.

Item 230 represents a photovoltaic cell. Item 250 represents an electronics circuit providing the same functions as described for the embodiment of FIG. 8. Item 200 is the momentary switch. Item 160 represents traditional LEDS. Item 170 represents an “O” ring to provide a seal between the cylindrical housing and the base. Item 280 represents the permanent adhesive.

FIG. 10 is a block diagram of a Traffic Alert System (TAS) that includes markers constructed in accordance with an embodiment of the invention. The block diagram of FIG. 10 depicts the electrical components and the hard-wired connections in Block A in accordance with an embodiment of the present invention and described for the embodiment of FIG. 8. A transparent cathode layer 226 and a transparent anode 224 are provided to drive the light-emitting layer 220. Item 254 is a MEMS accelerometer. Item 256 is an integrated circuit, which can be programmed to perform the functions described above and below.

Block B depicts the multiple wireless connections between the present invention and independent devices. These include but are not limited to remote sensors 400, vehicles 410, other markers 420, portable computers 430 and hand held remote controllers 440 using Bluetooth or similar technology that avoids spectrum licensing requirements and allows for adoption of widely available technology. Bluetooth uses the worldwide unlicensed frequency of 2.4 GHz that has a range of up to 100 meters depending on the class, can penetrate solid objects, is omni-directional and does not require line-of-sight positioning of connected devices which has the further advantage of assuring communication between devices that might have been displaced during an accident. The Bluetooth technology including software and hardware is widely available and very inexpensive and provides multiple layers of security. Also depicted is the wireless connection linking the TAS units to the Cospas-Sarsat Satellites or cellular services 450.

Block C depicts the secondary network connections for processing and distribution of the emergency alerts to Internet services 310, local emergency services 320 and via satellite to vehicle navigation systems 330.

In the event of activation of any one TAS marker, that marker will briefly broadcast an encoded and encrypted digital signal including its unique serial number. All other TAS markers programmed to respond to the specific digital code, for example that possibly have a sequential serial number within a certain number of the activating marker or within a limited range, would be activated to flash for a programmed specific time or until deactivated by another signal, thus isolating roads or opposite traffic lanes from each other as required, and preventing the theft and misuse of the markers.

A TAS marker can be manually activated by a momentary switch. The severity of the incident could be indicated by the number of times the switch is pressed, by direct impact sensing or when activated remotely by emergency personnel and roadwork crews for increased safety using hand held remote controllers 440. They could also be activated remotely by receiving a signal from independent sensors 400 such as, but not limited to those sensing poor road surface conditions such as snow, ice and water, limited visibility like fog, traffic traveling at unsafe high or low speeds and approaching trains at rail crossings. Vehicles 410 equipped with air bags could be modified to transmit an activation signal and other information described below on deployment to the TAS markers. Many newer vehicles already come equipped with Bluetooth communication technology, which could easily be integrated with air bag deployment to provide this signal. Emergency vehicle personnel and other authorities can remotely activate the TAS units around the last exits on roads such as United States interstate roads before the incident, thus warning drivers that it might be best to exit the road and find an alternate route or avoid entering the road.

Each TAS marker would have various parameters programmed into it after installation, such as a unique beacon identification serial number, flash frequency and color for distinguishing between lane markers and roadside markers and the duration before automatically turning off. Also instructions concerning whether to activate automatically at sundown and turn off at sunrise at places like work areas, and the option to deactivate the 406 MHz or Cellular alert systems when used for example on road cones and barrels. The markers could also be individually programmed to relay warning signals to other TAS markers 420 in the vicinity that might be unable to receive the signals from the originally activated marker because of physical or radio signal obstruction or propagation limits, thus providing a means to extend the number of units that are activated so adequate warning of danger ahead is provided. This relaying could also be useful when the original marker is geographically unable to transmit directly to the Cospas-Sarsat satellites or cell phone system so another TAS marker more favorably located can transmit the distress signal.

This programming could be done for example from an authorized vehicle while in motion using a widely available Bluetooth equipped laptop 430 and an interface software program. The laptop could be connected to an off-the-shelf Global Positioning System (GPS) unit to calculate the correct location or an approximate location of each TAS marker for transmission with its unique identifier and emergency contact information code to a Beacon Registration Database in a computer system 300. When at least three GPS satellites are not visible, most GPS units can calculate an estimated position based on recent speed and direction. It is preferable that the GPS units are of the type that includes for example the Wide Area Augmentation System (WAAS) in the United States, or in Europe the Euro Geostationary Navigation Overlay Service (EGNOS), as these provide for accuracy in the 3 meter range.

By using programmable TAS devices, the markers could be adjusted at any time to operate in an optimum fashion for the location and conditions, and to allow for the mass production of few hardware variations. Further, by not requiring each TAS unit to have GPS hardware and the 121.5 MHz homing signal hardware required by Personal Locator Beacons, additional cost and energy requirement savings are obtained and emergency aid response time is improved.

Since the TAS markers have transceiver abilities, maintenance vehicles could be outfitted with a Bluetooth enabled laptop computer 430 with propriety software to automatically interrogate the units for integrity of their circuitry, encoding, and battery charge and condition. The computer could also initiate a brief activation of the electroluminescent plastics for a quick visual inspection without the vehicle having to stop.

On activation in an emergency, a TAS marker is programmed to briefly transmit on 406 MHz a half second burst of data to the Cospas-Sarsat satellites 450 that includes a unique digitally encoded beacon identification serial number, the ID code of the sensor that activated the TAS marker, for example the TAS MEMS, the momentary switch or the ID code of the remote sensor and other data including that required by the Cospas-Sarsat satellites. These satellites relay this data to the Cospas-Sarsat earth receiving stations called Local User Terminals (LUTs) which automatically examine the beacon message and cross references the beacon identification serial number with the beacon registration database 300 to determine the geographical location of the TAS marker and the local emergency authorities 320 to automatically notify.

Alternately the emergency signal could be relayed via ground-based systems such as cellular telephone systems 450, however this would require extensive negotiations and hardware installations with many regional cellular companies worldwide which would be very expensive to implement. The Cospas-Sarsat system is already fully implemented covering 70% of the globe.

Other information that could be transmitted could indicate whether the marker has been activated by a maintenance test or by the number of times a momentary switch is pressed. Also remote sensors in vehicles could transmit to the TAS markers a unique vehicle identification code such as the registration or chassis number, the number of seats that had an air bag deploy and the G force experienced. The TAS markers would include this data in their distress signal. The LUTs or local emergency authorities could then automatically identify the owner of the vehicle and possibly the family medical providers so medical records can be checked to help facilitate quicker and better medical support. Most new cars only deploy air bags on seats that are occupied, so the number of people or possible casualties involved could be calculated and the possible severity of injuries could be estimated by the G forces calculated by the air bag deployment MEMS. General Motors has recently started implementing electronics in new vehicles with their “OnStar” system that calculates the severity of an incident and provides this information via cellular transmission to their control centers. This reliance on cellular systems has limitations in coverage, requires a monthly fee and is limited to the U.S. and Canada. An inexpensive unit of accelerometers and Bluetooth technology and possibly a manual or automatic means of determining occupancy numbers to interface with the present invention could be retrofitted to all vehicles. This data is critical for immediately activating the appropriate number and type of emergency personnel, providing cost savings and deploying such resources more effectively, especially when road conditions are bad and emergency personnel are stretched thin by multiple incidents. Existing ELTs and Personal Locator Beacons (PLBs) that use the Cospas-Sarsat system encode for the GPS position. Since the TAS markers are stationary, enhanced position data can be stored in a central beacon registration database and replaced with other data for example those outlined above, thus enhancing the usefulness of the present invention without adding to the data transmission and providing for a quicker and more appropriate response.

This puts the responsibility for programming the markers via a supplied software interface, maintenance and monitoring into the hands of local authorities, making the data more reliable, and the system less centralized. Thus the demands of the control system on a global basis would be considerably simpler and less expensive, as it can be almost completely automated even while the field system is deployed and modified. A ground monitoring system could also produce a graphical web presentation and relay the incident coordinates to Internet map and route providers 310 to enhance public trip planning, and to proprietary systems like the GM “OnStar” vehicle safety system or via satellite to GPS road navigators 330 such as those made by Garnin, providing drivers real time alerts of incidents even several miles away. The monitoring system could record all incidents, providing another tool to various authorities to better monitor their national roads for planning and safety improvements.

In-vehicle guidance systems can be used to complement this invention and improve safety. This invention could also improve the ability of such systems to define roadways.

In some embodiments, the present invention relates to a tape composed of photoluminescent and electroluminescent elements, and an electronic circuit for application to roadside markers, wherein the electronic circuit causes the electroluminescent element to emit electromagnetic radiation in the visual spectrum to alert oncoming traffic of an accident, road construction, an obstruction or other incident, and also in the radio spectrum for immediate remote sensing of an incident and location by traffic and emergency authorities. This is vital as medical help within the first hour, commonly known as the golden hour or critical hour, after injury is critical and every second in delay seriously affects the outcome of trauma.

The invention allows for the continued use and improvement of most existing roadside markers or, in the case of lane markers, the invention can be implemented using minor modifications to existing devices.

The markers can be constructed using cost-effective automated production of each of the flexible film layers. The layers can be formed into rolls and the roll layers can be laminated into a tape, using a web manufacturing process known as roll-to-roll (R2R). This is desirable as it uses fewer toxic solvents and cleaners. The manufacturing process can be carried out with many recyclable materials and it eliminates many sources of defects. Varying lengths of the laminated structure can be produced with the same production methods. Additionally, cost savings are realized in storage and distribution, as well as by application of the invention to various roadside markers by the original equipment manufacturers during manufacture, and field application where much of it can be automated with machines.

This invention can provide a cost-effective road hazard alerting system that will operate with very low power consumption. The electronics include communication technology and are programmable to provide a Traffic Alert System or TAS. In addition, the roadside markers can provide a means for monitoring vehicle incidents for road safety improvements.

The Traffic Alert System can be implemented by placing a plurality of roadside markers in an area, wherein each of the roadside markers includes a light-emitting element, an electronic circuit connected to the light-emitting element, a battery connected to the electronic circuit, and a photovoltaic cell electrically connected to the battery; and causing the electronic circuit in at least one of the roadside markers to transmit a signal to a remote location to indicate the presence of an accident or other condition.

The electronic circuit can be used to operate the light-emitting element in a particular mode based on signals received by the electronic circuit. The marker can be remotely programmed and its operation can be remotely tested.

The signal transmitted by the roadside marker can include a unique serial number for identifying the location of the marker. The signal transmitted by the roadside marker can also include a unique code number of a sensor that is used to actuate the marker. For example the sensor can be a vehicle sensor that produces a signal indicating a unique vehicle identification number, a number of occupants of the vehicle, and/or an indication of the severity of a vehicle accident. The unique vehicle identification number can be used to determine at least one of: vehicle ownership, residence, and medical contact data.

The present invention is superior to the prior art in that all the components including the power source are self-contained, are lightweight, flexible, more durable and provides many new features not previously available. The use of electronics allows for the control of the colors and also the duration of flashes, which saves energy and is more noticeable to the eye.

Whereas particular embodiments of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention. 

1. A roadside marker comprising: a light-emitting element capable of emitting multiple colors; an electronic circuit connected to the light-emitting element, wherein the electronic circuit controls the light-emitting element to emit different colors in response to signals received by the electronic circuit; a battery connected to the electronic circuit; and a photovoltaic cell electrically connected to the battery.
 2. The roadside marker of claim 1, wherein the electronic circuit includes a receiver for receiving externally supplied signals.
 3. The roadside marker of claim 1, further comprising: an antenna providing a reflective backing for the photovoltaic cell.
 4. The roadside marker of claim 1, wherein the light-emitting element, the electronic circuit, the battery, and the photovoltaic cell are each mounted in layers of a flexible thin film tape.
 5. The roadside marker of claim 4, wherein the tape further comprises an antenna electrically connected to the electronic circuit.
 6. The roadside marker of claim 1, wherein the electronic circuit causes the light-emitting element to emit electromagnetic radiation in the infrared spectrum.
 7. The roadside marker of claim 1, wherein the electronic circuit comprises an integrated circuit including at least one of: a microprocessor, a rewritable memory, a modulator and a transceiver.
 8. The roadside marker of claim 1, wherein the electronic circuit is structured and arranged to be remotely operated by: remote signals from other devices.
 9. The roadside marker of claim 1, wherein the electronic circuit can be remotely programmed.
 10. The roadside marker of claim 1, further comprising a layer of photoluminescent material.
 11. The roadside marker of claim 1, further comprising an optically transparent protective film adjacent the light-emitting element.
 12. The roadside marker of claim 1, further comprising an adhesive layer adjacent an exterior surface of the marker, for mounting the marker in a substantially vertical position.
 13. (canceled)
 14. (canceled)
 15. (canceled)
 16. A method comprising the steps of: placing a plurality of roadside markers in an area, wherein each of the roadside markers includes a light-emitting element, an electronic circuit connected to the light-emitting element, a battery connected to the electronic circuit, and a photovoltaic cell electrically connected to the battery; and causing the electronic circuit in at least one of the roadside markers to transmit a unique identification signal to a remote location to indicate the presence of an accident or other condition, the remote location including a database relating the unique identification signal to the location of the roadside markers.
 17. The method of claim 16, further comprising the step of: using the electronic circuit to operate the light-emitting element in a particular mode based on signals received by the electronic circuit.
 18. The method of claim 16, further comprising the step of: remotely programming the electronic circuit.
 19. The method of claim 16, further comprising the step of: remotely testing the operation of the roadside marker.
 20. (canceled)
 21. The method of claim 16, wherein the signal transmitted by the roadside marker includes a unique code number of a sensor actuating the marker.
 22. The method of claim 16, wherein the signal transmitted by the roadside marker includes a unique code number from a vehicle sensor indicating at least one of: a unique vehicle identification number, a number of occupants of said vehicle, and an indication of the severity of a vehicle accident.
 23. The method of claim 22, wherein the signal transmitted by the unique vehicle identification number is used to determine at least one of: vehicle ownership, residence, and medical contact data.
 24. A roadside marker comprising: a light-emitting element; an electronic circuit connected to the light-emitting element; a battery connected to the electronic circuit; a photovoltaic cell electrically connected to the battery; and an accelerometer for activating the electronic circuit when the marker experiences an acceleration.
 25. A roadside marker comprising: a light-emitting element; an electronic circuit connected to the light-emitting element; a battery connected to the electronic circuit; and a photovoltaic cell electrically connected to the battery; wherein the light-emitting element comprises an electroluminescent material positioned such that photons pass through the electroluminescent material to excite electrons in the photovoltaic cell.
 26. The roadside marker of claim 1, wherein the light-emitting element comprises a quantum dot tunable electroluminescent semiconductor.
 27. The roadside marker of claim 1, wherein the electronic circuit causes the light-emitting element to emit electromagnetic radiation at different frequencies based on road conditions.
 28. The roadside marker of claim 1, wherein the light-emitting element comprises polymer light-emitting diodes.
 29. The roadside marker of claim 1, wherein the photovoltaic cell comprises a nanostructured quantum dot radiation tuned semiconductor.
 30. The roadside marker of claim 1, wherein the electronic circuit activates the light-emitting element in response to an amount of light received by the photovoltaic cell. 